Explain the significance of sodium, potassium, magnesium and calcium in biological fluids.

(a) Human muscle fluid 6.83:  pH = 6.83 pH = – log [H+]  6.83 = – log [H+]  [H+] =1.48 × 10–7 M (b) Human stomach fluid, 1.2:  pH =1.2 1.2 = – log [H+]  [H+]...

(b) calcium and phosphorus

(i) Sodium oxide                 → Na2O  (ii) Aluminium chloride       → AlCl3  (iii) Sodium suphide           → Na2S  (iv) Magnesium hydroxide → Mg(OH)2

(a) Magnesium chloride →MgCl2  (b) Calcium oxide →CaO  (c) Copper nitrate →Cu(NO3)2  (d) Aluminium chloride →AlCl3  (e) Calcium carbonate →CaCO3

Number of moles 12 / 24 = 0.5 mol 

A Mg2+ ion and Mg atom differ by two electrons.  103 moles of Mg2+ and Mg atoms would differ by  103 × 2 moles of electrons  Mass of 2 ×103 moles of electrons...

(c) Gases and liquids behave like fluids

When a body moves through a fluid, it experiences an opposing force which tries to oppose its motion through the fluid. This opposing force is known as the drag force....

(C) calcium carbonate Marble contains calcium carbonate and its chemical formula is CaCO3.​

i. The reaction in which one reactant gets oxidised and the other reactant gets reduced is called redox reaction. ii. When a magnesium ribbon burns in air with a dazzling flame...